Early life and genetic factors hasten onset of eosinophilic esophagitis

Published online: October 23, 2020

Eosinophilic esophagitis (EoE) is a rare allergic condition in which eosinophils, a type of white blood cells, react to foods and build up in the esophagus. This eosinophilic build-up affects the function of the esophagus, often leading to symptoms including pain, difficulty swallowing and failure to thrive in children and pain, difficulty swallowing and food getting stuck (impaction) in adults. EoE is a progressive, lifelong condition for which there is no FDA-approved treatment and is managed by restricting foods in the diet and using swallowed steroids.

Lyles et al. investigated the timing of the onset of EoE to gain insight on what early life and genetic factors are involved in developing EoE and whether timing of onset affects the severity of the disease. Their findings, published in The Journal of Allergy and Clinical Immunology (JACI), provide needed perspective into the early circumstances of EoE development, as some individuals with EoE may not be diagnosed with EoE until mid-to-late childhood or adulthood.
Lyles et al. reviewed available patient data to compare aspects of two patient groups: 1) patients with EoE diagnosed very early (within the first 12 months of life) and 2) patients with EoE diagnosed late (from 14-18 years of age). These two groups were compared by medical record, histology (EoE Histology Scoring System), endoscopy (Endoscopic Reference Score), gene expression (EoE Diagnostic Panel) and genetic association (EoE genotype repositories).

The researchers found that diagnosis of EoE in children was most often within the first 2 years of life. Notably, patients with very early diagnosis of EoE (within the first 12 months of life) were more commonly delivered by Caesarean section and were more likely to have success in managing their condition with dietary restriction than were patients with late diagnosis of EoE (from 14-18 years of age). In terms of histology and endoscopy, patients with very early diagnosis of EoE had greater components of eosinophil inflammation and expansion of cells within the basal zone of the esophageal lining, whereas patients with late diagnosis of EoE more commonly had narrowing of the esophagus (stricture) and higher scores for endoscopy, suggesting a worse condition. Interestingly, gene expression in EoE (the EoE transcriptome) was largely similar between these groups, though patients with very early diagnosis of EoE more commonly had genetic variations in the gene for calpain 14 (CAPN14), which has been previously demonstrated to be associated with risk for EoE.

Lyles et al. concluded that diagnosis of EoE commonly occurs early in life. This disease entity is referred to as very early onset EoE or vEoE. Importantly, very early onset EoE is not a more severe form of EoE and responds to standard therapy without early evidence for complications. Though the molecular pathogenesis for pediatric EoE was similar irrespective of early or late onset, Caesarean delivery and genetic variation in calpain 14 (CAPN14) may promote earlier disease development.

The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.

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